Sod knife for anhydrous ammonia

ABSTRACT

A constant attitude sod knife for injection of anhydrous ammonia to the soil which includes a ground opening blade structure, a gas injection tube disposed at the heel or trailing of the blade and covered by a diffusion director vane or wing and subsequently by a tamping or compaction vane or wing which serves to restrict emission of gaseous materials to the atmosphere and a spring biased carriage facilitating a constant running attitude whereby the blade may change elevation without changing attitude, and an impact disengaging connection and depth control wheel for the carriage.

United States Patent Hansen 14 1 Dec. 26, 1972 54 SOD KNIFE FORANHYDROUS 2,439,743 4/1948 McEwen ..111/7 AMMONIA 2,724,318 11/1955Erickson 6161 ..172/678 2,874,656 2 1959 a 11 ..111 7 Invenlofl Clarence118115611, East Lansing, 2,988,026 641961 1122mm ..111/7 Mich. 731Assignee: Board 61 Trustees 6111616111 6 sum Bagwi" University, EastLansing, Mich.

[22] Filed: July 1, 1970 [21] Appl. No.: 51,644

[52] U.S. Cl ..111/7, 1721678 [51] Int. Cl ..A0lc 23/02 [58] Field ofSearch ..l l l/6-7, 85;

[56] References Cited UNITED STATES PATENTS 2,842,077 7/1958 Morrison..111/7 3,296,985 l/l967 Shelton ..l 1 H7 2,849,969 9/l958 Taylor..111/7 Attorney-Miller, Morriss, Pappas &- McLeod [57] ABSTRACT Aconstant attitude sod knife for injection of anhydrous ammonia to thesoil which includes a ground opening blade structure, a gas injectiontube disposed at the heel or trailing of the blade and covered by adiffusion director vane or wing and subsequently by a tamping orcompaction vane or wing which serves to restrict emission of gaseousmaterials to the atmosphere and a spring biased carriage facilitating aconstant running attitude whereby the blade may changeelevation withoutchanging attitude, and an impact disengaging connection and depthcontrol wheel for the carriage.

4 Claims, 6 Drawing Figures PATENTEDnEms 4912 SHEET 2 BF 2 F M 9 a SODKNIFE FOR ANI-IYDROUS AMMONIA The present invention relates to animproved sod knife or a ground opening device by which means a gaseousor liquid material such as fertilizer, fumigant or conditioner, forexample, anhydrous ammonia, is injected into the opened soil, is urgedin place to selectively propogate or diffuse, and is then substantiallytamped by sub-surface tamping to allow slow dispersion outwardly fromthe situs of entry. The present invention proposes to nest the deliverytube along the trailing edge of the vertical sod knife or blade to apoint adjacent the heel of the blade or at the trailing edge at thepoint of furrow closure behind the blade opening. A diffusion deflectorvane or wing is provided above the emission point to laterally diffusethe liquid or gaseous material into the earth flanking the blade madefurrow or opening and to restrict vertical emission along the trailingedge of the blade above the tube portals. Then a tamping deflector orplate is provided above and trailing the diffusion deflector which tendsto close and tamp the furrow or opening behind the blade move ment at asub-surface level. To accomplish this the blade structure of theapplicator required change from prior art approaches and the carriagemechanism required adapting so that the running attitude of the bladeremains reasonably constant despite local changes in depth. The runningdepthis generally controlled by a ground engaging gauge wheel. The gaugewheel is preferably trailing the blade to accomplish a surface tamp ofthe furrow. The device is protected by a suitable impact disconnectmeans such as a shear bolt or shear pin which prevents serious damage ascould result from the blade encountering a boulder, rock, or overly hardground. In exceptionally hard ground the knife performs best when leadby a groundopening coulter wheel.

The prior art is fairly well represented by the devices seen in the US.Pat. Nos. to: Taylor 2,849,969, Johnson 3,038,424, Johnston 3,188,989,Heckathorn 2,988,026, and Shelton 3,296,985.

The use of anhydrous ammonia and liquid or gaseous fertilizers orfumigants requires the injection of material into the earth and theirdisposition requires control against loss to the atmosphere.Accordingly, many expedients have been used to accomplish injection intothe earth without loss. Every device tested to date has had seriousdrawbacks related to the fact that terrain differences or conditionsresult in a changing blade attitude and where this has been possible tocontrol, the escape of gaseous or liquid fertilizer has been upwardalong the trailing edge of the blade and before the furrow can beclosed. The present device accordingly provides a running fixed attitudeconstruction allowing the use of two separate fixed angle plate-likeelements. The lower one is a deflector wing element for lateraldiffusion and for interrupting the upward travel of the gas or liquidand the other plate-like element overlaps the lower deflector in atrailing sequence sense to provide a gentle but firm running tampingclosure of the furrow below the surface of the earth but above thediffusion point at the heel of the blade.

Accordingly, the principal object of the present invention is to providea soil knife which presents a constant running attitude while varying asto depth position. A collateral object is the provision of a soil knifefor liquid and gaseous fertilizers and soil conditioners in which a pairof plate elements (deflector and tamper) overhang the emission pointeach at different fixed attitudes. Another object is to provide a shearpin protected blade and carriage so that disabling obstacles will notseriously impair the carriage performance and construction.

In the drawings:

FIG. 1 is a perspective view of the sod knife of the present inventionand indicating the attachment of the knife to a gang draw bar andindicating the tubular feed connection for liquid orgaseous fertilizer,soil fumigant, or soil conditioner.

FIG. 2 is a side elevation view of the sod knife seen in FIG. 1 andindicating the insertion of the blade into the ground and indicating thefixed attitude of the blade while the carriage position is variable.

FIG. 3 is a partial cross section elevation view taken on the linelII-lll of FIG. 2 and indicating the shear pin construction andorienting the blade in relation to the feed tube.

FIG. 4 is a partial enlarged cross section elevation view taken on theline IVIV of FIG. 3 and indicating the relative positions of tube,diffuser or deflector and tamper.

FIG. 5 is a cross section elevation view taken on the line V-V of FIG. 2and indicating the carriage construction and indicating the rollerbuttressing of the mounting shaft.

FIG. 6 is a full section elevation view of the carriage taken on theline Vl-Vl of FIG. 5 and best indicates the spring bias application offorce urging the mounting shaft toward the earth while allowing theshaft to swivel and move against the spring bias and against thebuttress of the rollers.

GENERAL DESCRIPTION The sod knife of the present invention is an earthopening blade which is provided with a feed tube which parallels theback or trailing edge of the blade and is secured thereto. A lowerdiffusion plate is provided in a diving attitude over the emission pointof the tube adjacent the heel of the blade, and a tamping plate ispositioned above and rearwardly of the emission point and above thediffusion plate and at a climbing angle or attitude to accomplishsubsurface tamping of the furrow.

A carriage assembly is provided which is rigidly attachable to a drawbar element pulled by a prime mover or tractor. The carriage assemblyprojects from the bar at a selected fixed angle and includes journalmeans which support a blade mounting shaft for rotation on the shaftaxis and for axial linear movement. The carriage also includes a springwhich applies a force directing the shaft downwardly toward engagementwith the earth. A knife supporting arm projects radially from the end ofthe mounting shaft. The arm is bifurcated to receive therebetween theknife or blade. Over the end of the arm the gauge wheel clevis assemblyextends and a pair of bolts in spaced relation through clevis assembly,arm and blade supports the gauge wheel and blade in fixed relation tothe arm. One of the bolts is a shear pin calculated to shear if theblade strikes an object such as a boulder and without riding over theobstacle. Other means of stress relieving may be used to prevent impactinjury and where exceptionally heavy ground is encountered a coulterwheel may be used to lead the blade to pre-open the ground.

The gauge wheel pilots the blade in a relationship to the earth toprovide a reasonably constant blade elevation and as will be seen toprovide a following surface tamp. The wheel and blade on'shearing of theshear pin bolt are pivotal on the remaining bolt, thus freeingthemselves of being a rigid extension of the arm, and damage is therebyavoided. This provides an overload disconnect against impact loading orthe like. Where the wheel engages irregularities in the earth it mayrise and when it does so the arm arises with the wheel and the shaftmoves linearly in its journal against the spring bias so that the bladeattitude in the earth remains fixed, although the depth of the blade mayvary somewhat with terrainirregularities. The spring bias urges fulldepression in the earth. A tube welded, brazed or otherwise affixed tothe backside or heel of the knife blade and terminates at the lower endadjacent the bottom of the blade and at the upper end extends above theblade to provide a nipple for attachment of a feed hose. Two plate-likeelements extend laterally from the blade, the lower or deflector platebeing the larger of the two plates and at its leading edge beingdisposed downwardly fromhorizontal thereby guiding the blade tipdownwardly in a diving attitude. The deflector plate extends rearwardlybeyond the tube. The upper or tamping plate is oriented upwardly at aslight angle in a climbing attitude partially counteracting the tendencyof the lower plate to plunge the blade downwardly. This upper plate,having a lower trailing edge which lags behind the lower plate,accomplishes a sub-surface tamping and forcefully tamps the earth intothe earth fissure formed by the action of the blade and further tampingis accomplished at the surface by the gauge wheel. Thus the entirestructure provides a fixed attitude for the deflector and tamper plateson the blade and the plates are counterpoised in respect to each otherand both overlap the tube and the compaction or tamping plate overlapsthe diffusion or deflector plate in prevention of the pressurizedinjectant liquid or gaseous material (fertilizer or fumigant, forexample) from escaping upwardly along the trailing edge of theblade asis consistently observed in the known prior art. The plates aregenerally concavo-convex, the concave side facing downwardly. The anglesof attack of the two plates can be varied to suit ground conditions butthe lower plate is in diving attitude while the upper or tamping plateis in climbing attitude. Accordingly, the sod knife of the presentinvention accomplishes a highly efficient introduction of pressurizedliquids and gases into a dynamic ground opening to achieve good lateraldiffusion and firm sub-surface trailing tamp.

SPECIFIC DESCRIPTION By reference first to FIG. 1 the preferredembodiment of the invention is best seen as a sod knife assembly 11secured to a draw bar 12 by the carriage assembly 13 which supports andjournals the blade mounting shaft 14. The shaft 14 is secured adjacentits lower terminal end to a knife support arm 15. The arm 15 secures thesod knife 16 and the gauge wheel 17 for coordinated movement with shaft14 and rearwardly of the shaft 14. The wheel 17 is secured to a bracketextension 18 which forms a clevis connection. One of the fastening means19 is a shear-pin which upon shear failure allows the wheel 17, bracket18 and knife 16 to rotate on the pivot point of fastener 20. The sodknife 16 comprises a ground opening blade 21 which is preferably arcuatealong the sharp leading edge thereof and the trailing edge issubstantially blunt or concave in cross section to nestably receive andprotect a delivery tube 22 which is brazed, welded orotherwise securedthereto and which tube 22 terminates adjacent the heel 23 of the blade21. There are openings through tube 22 at the lower terminal endadjacent the heel of the blade 21 through which material is passed intothe soil as a furrow is opened by the movement of the blade 21. In aplane transverse to the plane of theblade 21 and at a slight divingattitude is a diffusion plate or wing 24 which extends laterally andrearwardly of the lower terminal end of the tube 22. This deflector ordiffusion plate 24 is brazed, welded or otherwise secured to the cheeksof the blade 21 and straddles the tube 22 providing a physical barrierto gas or liquid flow tending to travel upwardly along the trailing edgeof the blade 21. In cross section the diffusion plate 24 is slightlyconcave-convex with the concave side downward. In manufacture a splittube forming the plate 24 is bifurcated longitudinally to straddle theblade 21 and tube 22 and is then'brazed to the blade 21 and closed onthe tube 22 as shown. At a spaced interval above the diffusion plate 24is a second or upper plate designated as'a tamping wing or plate 25.This tamping plate 25 is constructed like the diffusion or deflectingplate 24 except that its angle of attack is a climbing attitudereferenced to forward movement of the blade 21 and as can be seen thetamping plate 25 is extended to termination rearwardly and above thedeflector or diffusion plate'24. Thus the action of the tamping platetrailing the blade 21 and diffusion plate 24 is to provide a sub-surfacetamping of soil which locally closes the furrow and prevents prematureescape of the fumigant or fertilizer injected through the tube 22. Itwill be appreciated that various angles of dive and climb may beprovided in respect to the lower diffusion plate 24 and. the uppertamping plate 25 respectively and the selection is in relation to theheaviness or lightness of the soil to be treated. The preferred divingattitude of the diffusion plate 24 is between 0 and 10 from horizontal.The preferred climbing attitude of the upper tamping plate 25 is alsobetween 0 and 10 Under average soil conditions best results are obtainedwith the diving attitude of plate 24 at 7 and the climbing attitude ofthe tamping plate 25 at 5 from horizontal. The tube 22 is connected to asupply source line 224 as by clamp 22b and the line 22a is connected toa supply tank, not seen.

Since optimum performance is referenced to a horizontal movement of theblade 21 in a vertical crevice it is desireable to assure that theattitude of the blade 21 in moving through soil is relatively constant.Hence the carriage 12 and arm 15 on shaft 14 support the sod knife 16 ata relatively constant depth established by the gauge wheel 17. The shaft14 is journalled in the carriage 13 at a slope or angle as seen at about60 to the horizontal at the included angle of projected shaft 14 andearth. The shaft 14 is allowed to reciprocate axially against the biasof spring 26 acting between the shaft 14 and carriage 13. In addition,as will be seen, the shaft 14 can turn on its axis so as to and movearound obstacles and over obstacles as may be encountered. The spring 26urges return to the setting required and allows a running flexure asbetween the horizon of bar 12 and soil surface contact of gauge wheel17.

In FIG. 2 the flexural action on the spring 26 can best be seen and thephantom lines indicate change of position in an elevational sensewithout changing the running attitude of the sod knife 16. The rollerjournals or anti-friction thrust buttresses 27 and 28 are located in therectangular or box frame 29 of carriage l3 and details of the clamp 30providing attachment to the rectangular bar 12 are best seen. A singlebar 12 drawn by a tractor can pull a plurality of knives 16. Hence thecarriage 13 is secured against rotation on the bar 12 except as torsionmay occur in extreme drag condition. The construction of thrust bracket31 is also best appreciated in the FIG. 2 secured to the upper terminalend of the shaft 14 and being adjustably connected to the tension spring26 by hook 32. The tube 22 is connected to flexible delivery line 22a bytubing clamp 22b and the line 33 connects to a source of liquid orgaseous fumigant, fertilizer, or soil conditioner. The constant attitudediving angle A is shown and climb attitude angle B is also shown.

In FIG. 3 the journal construction of the gauge wheel 17 is revealed.The journalling 33 is self contained in capped concentric sleeves andsecured to the clevis bracket 18 by the bolt 34. The shear pin 19 isseen as a brass or bronze bolt and the pivot bolt or fastener 20 can beseen beneath it. The blade 16 is thus secured between the arms 15,bracket 18 and in fixed position by the fasteners 19 and 20 through arms15, bracket 18, and blade 16. The delivery tube 22 is visible securedalong the trailing edge of the blade 16. The setting of the gauge wheel16 establishes maximum penetration depth and provides a surface tamp.

FIG. 4 best reveals the details of the sod knife 16 in the area of gasor liquid emission at the lower terminal end of tube 22 at the heel 23of the blade 21. The plunging attitude of the diffusion blade 24prevents gases or liquids from following up along the trailing edge ofthe blade 21 but provides a deflector to diffuse the materials outwardlyfrom tube openings 35 extending radially from the terminal end of thetube 22. The plug 36 is used to facilitate radial diffusion but can beremoved as desired. In FIGS. 2 and 4 the dynamics of the two plates 24and 25 can be best appreciated. Tamping plate 25 compresses the earth atand above the fissure created by the blade 21 and the diffusion plate 24has deflected the emitted material away from the trailing edge of theblade 21 in prevention of escape to atmosphere up the back of the blade21.

FIGS. 5 and 6 best express the construction of carriage l3 and theconcave faced roller journals 27 and 28 cradle the shaft 14 and allow itto move axially against the spring bias of spring 26. This allows theshaft 14 to turn and provides a swivelling action for the trailed sodknife 16. In the FIG. 6 the spring hanger tab 37 provides a lowerfastener for the tension spring 26. The set screw 38 in the thrustbracket 31 provides an adjustable connection of bracket 31 to shaft 14.

In operation, the first observed result using the sod knife 16 was theavoidance of visible escape of gases,

for example, anhydrous ammonia. On perfectly level ground the knife 16worked beautifully in the ranges indicated without unusual stressing ofthe tractor moving the gang bar 12 on which plural of the knives 16 weremounted. As terrain attitudes shifted beyond the desired fixed attituderelations the knives l6 worked less satisfactorily and the describedcarriage structure was devised to assure relatively constant runningattitude of the blade. Then optimum performance resulted. In itsoperational setting the tube 22 is connected to a source of fumigant,conditioner, or fertilizer which is usually under pressure in a pressurevessel or container. As seen in FIG. 1 the feed lines from the storagecontainer are secured as by tubing clamps to the projecting upper endsof the tubes 22. These feed lines may be suitably valved as is wellknown in the art.

Having thus described my invention, others skilled in the art willreadily perceive improvements and modifications and such improvementsand modifications are intended to be included in the spirit of thepresent invention subject to the scope of my hereinafter appendedclaims.

lclaim:

l. A constant attitude sod knife applicator comprising:

a carriage;

a clamp securing said carriage to a horizontal draw bar againstrotation;

roller journals in said carriage providing a guide path at about 60 tohorizontal;

a shaft in said carriage and on said journals whereby said shaft ismovable axially and rotatable on its axis;

a spring bias between said shaft and said carriage urging said shaftdownwardly in respect to said carriage;

an arm secured to the lower end of said shaft and extending radiallytherefrom;

a sod knife blade dependingly secured to said arm;

a tube extending down the trailing edge of said blade and open at thelowermost end adjacent the heel of said blade;

a diffusion plate on said blade in plane transverse to the plane of saidblade and in a diving attitude between about 0 and 10 and extendingbeyond the trailing edge of said blade and slightly above the heel of ofsaid blade;

a tamping plate on said blade in a plane transverse to the plane of saidblade and in a climbing attitude, the trailing end of said tamping platetrailing said diffusion plate and said tamping plate located above andto the rear of said diffusion plate; and

a depth gauging element secured to said blade and trailing said blade ina surface tamping relation thereto.

2. A soil injecting sod knife combination comprising:

a ground opening blade vertically disposed for movement through theearth and having a leading and trailing edge and a heel at the lower endof said trailing edge;

a tubular delivery element secured to the trailing edge of said bladeand the lower terminal end of said tubular element having an openingtherethrough adjacent said heel of said blade;

a diffusion plate in a plane transverse to the plane of said blade andsecured thereto and extending therefrom and in a diving attitude withrespect to horizontal and immediately above said lower terminal end ofsaid tubular member and extending rearwardly of said blade and saidtubular element;

and

a tamping plate positioned on said blade spaced above and partiallyoverlapping said first diffusion plate and secured to said blade in aplane transverse to the plane of said blade and in a climbing attitudewith respect to horizontal and extending above and behind said diffusionplate and said tu-

1. A constant attitude sod knife applicator comprising: a carriage; aclamp securing said carriage to a horizontal draw bar against rotation;roller journals in said carriage providing a guide path at about 60* tohorizontal; a shaft in said carriage and on said journals whereby saidshaft is movable axially and rotatabLe on its axis; a spring biasbetween said shaft and said carriage urging said shaft downwardly inrespect to said carriage; an arm secured to the lower end of said shaftand extending radially therefrom; a sod knife blade dependingly securedto said arm; a tube extending down the trailing edge of said blade andopen at the lowermost end adjacent the heel of said blade; a diffusionplate on said blade in plane transverse to the plane of said blade andin a diving attitude between about 0* and 10* and extending beyond thetrailing edge of said blade and slightly above the heel of of saidblade; a tamping plate on said blade in a plane transverse to the planeof said blade and in a climbing attitude, the trailing end of saidtamping plate trailing said diffusion plate and said tamping platelocated above and to the rear of said diffusion plate; and a depthgauging element secured to said blade and trailing said blade in asurface tamping relation thereto.
 2. A soil injecting sod knifecombination comprising: a ground opening blade vertically disposed formovement through the earth and having a leading and trailing edge and aheel at the lower end of said trailing edge; a tubular delivery elementsecured to the trailing edge of said blade and the lower terminal end ofsaid tubular element having an opening therethrough adjacent said heelof said blade; a diffusion plate in a plane transverse to the plane ofsaid blade and secured thereto and extending therefrom and in a divingattitude with respect to horizontal and immediately above said lowerterminal end of said tubular member and extending rearwardly of saidblade and said tubular element; and a tamping plate positioned on saidblade spaced above and partially overlapping said first diffusion plateand secured to said blade in a plane transverse to the plane of saidblade and in a climbing attitude with respect to horizontal andextending above and behind said diffusion plate and said tubularelement, the distance between and trailing relationship of said platesbeing such that soil diffused upwardly by said diffuser is compactedbetween said diffuser and said tamping plate.
 3. The combination asexpressed in claim 2 wherein said tamping plate and said diffusion platehave concavo-convex surfaces and the concave portion is faceddownwardly.
 4. The combination as expressed in claim 3 wherein saidtamping plates and said diffusion plates are integral with said groundopening blade.